toolkit/xre/nsGDKErrorHandler.cpp

   1 /* -*- Mode: C++; tab-width: 40; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #include "nsGDKErrorHandler.h"
   7
   8 #include <gtk/gtk.h>
   9 #ifdef MOZ_X11
  10 #  include <gdk/gdkx.h>
  11 #endif
  12 #include <errno.h>
  13 #include <stdlib.h>
  14 #include <string.h>
  15
  16 #include "nsDebug.h"
  17 #include "nsString.h"
  18 #ifdef MOZ_X11
  19 #  include "nsX11ErrorHandler.h"
  20 #endif
  21
  22 #include "prenv.h"
  23
  24 /* See https://bugzilla.gnome.org/show_bug.cgi?id=629608#c8
  25  *
  26  * GDK implements X11 error traps to ignore X11 errors.
  27  * Unfortunatelly We don't know which X11 events can be ignored
  28  * so we have to utilize the Gdk error handler to avoid
  29  * false alarms in Gtk3.
  30  */
  31 static void GdkErrorHandler(const gchar* log_domain, GLogLevelFlags log_level,
  32                             const gchar* message, gpointer user_data) {
  33 #ifdef MOZ_X11
  34   if (strstr(message, "X Window System error")) {
  35     XErrorEvent event;
  36     nsDependentCString buffer(message);
  37     char* endptr;
  38
  39     /* Parse Gdk X Window error message which has this format:
  40      * (Details: serial XXXX error_code XXXX request_code XXXX (XXXX) minor_code
  41      * XXXX)
  42      */
  43     constexpr auto serialString = "(Details: serial "_ns;
  44     int32_t start = buffer.Find(serialString);
  45     if (start == kNotFound) {
  46       MOZ_CRASH_UNSAFE(message);
  47     }
  48
  49     start += serialString.Length();
  50     errno = 0;
  51     event.serial = strtol(buffer.BeginReading() + start, &endptr, 10);
  52     if (errno) {
  53       MOZ_CRASH_UNSAFE(message);
  54     }
  55
  56     constexpr auto errorCodeString = " error_code "_ns;
  57     if (!StringBeginsWith(Substring(endptr, buffer.EndReading()),
  58                           errorCodeString)) {
  59       MOZ_CRASH_UNSAFE(message);
  60     }
  61
  62     errno = 0;
  63     event.error_code = strtol(endptr + errorCodeString.Length(), &endptr, 10);
  64     if (errno) {
  65       MOZ_CRASH_UNSAFE(message);
  66     }
  67
  68     constexpr auto requestCodeString = " request_code "_ns;
  69     if (!StringBeginsWith(Substring(endptr, buffer.EndReading()),
  70                           requestCodeString)) {
  71       MOZ_CRASH_UNSAFE(message);
  72     }
  73
  74     errno = 0;
  75     event.request_code =
  76         strtol(endptr + requestCodeString.Length(), &endptr, 10);
  77     if (errno) {
  78       MOZ_CRASH_UNSAFE(message);
  79     }
  80
  81     constexpr auto minorCodeString = " minor_code "_ns;
  82     start = buffer.Find(minorCodeString, endptr - buffer.BeginReading());
  83     if (!start) {
  84       MOZ_CRASH_UNSAFE(message);
  85     }
  86
  87     errno = 0;
  88     event.minor_code = strtol(
  89         buffer.BeginReading() + start + minorCodeString.Length(), nullptr, 10);
  90     if (errno) {
  91       MOZ_CRASH_UNSAFE(message);
  92     }
  93
  94     event.display = GDK_DISPLAY_XDISPLAY(gdk_display_get_default());
  95     // Gdk does not provide resource ID
  96     event.resourceid = 0;
  97
  98     X11Error(event.display, &event);
  99   } else
 100 #endif
 101   {
 102     g_log_default_handler(log_domain, log_level, message, user_data);
 103     MOZ_CRASH_UNSAFE(message);
 104   }
 105 }
 106
 107 void InstallGdkErrorHandler() {
 108   g_log_set_handler("Gdk",
 109                     (GLogLevelFlags)(G_LOG_LEVEL_ERROR | G_LOG_FLAG_FATAL |
 110                                      G_LOG_FLAG_RECURSION),
 111                     GdkErrorHandler, nullptr);
 112 #ifdef MOZ_X11
 113   if (PR_GetEnv("MOZ_X_SYNC")) {
 114     XSynchronize(GDK_DISPLAY_XDISPLAY(gdk_display_get_default()), X11True);
 115   }
 116 #endif
 117 }